Moisture vapor permeable carpet underlay

Abstract

A carpet underlay that is liquid impermeable and moisture vapor permeable comprising a foamed cushion and a barrier film affixed to the side of the foamed cushion in contact with the carpet, the barrier film being impermeable to liquids and permeable to moisture vapor and comprising copolymer that comprises polytrimethylene ether soft segments and hard segments selected from the group consisting of polyester, polyamide, polyurethane and polyurethane-urea.

1 . A carpet underlay comprising:
 (a) a foamed cushion having opposite first and second planar sides; and   (b) at least one barrier film affixed to the first side of the foamed cushion, the barrier film being substantially impermeable to liquids and permeable to moisture vapor and comprising copolymer that comprises polytrimethylene ether soft segments and hard segments selected from the group consisting of polyester, polyamide, polyurethane and polyurethane-urea.   
   
   
       2 . The carpet underlay of  claim 1  wherein the foamed cushion comprises foamed polyurethane, or polyurethane urea comprising poly(trimethylene ether) blocks as a soft segment. 
   
   
       3 . The carpet underlay of  claim 1  wherein the barrier film comprises polytrimethylene ether ester elastomer comprising from about 80 to about 5 weight % polytrimethylene ether ester soft segment and about 20 to about 95 weight % alkylene or phenylene ester hard segment. 
   
   
       4 . The carpet underlay of  claim 3  wherein the hard segment comprises an ester of at least one dicarboxylic acid selected from the group consisting of phthalic acid, isophthalic acid and terephthalic acid. 
   
   
       5 . The carpet underlay of  claim 1  wherein the barrier film comprises from about 40 to about 80 weight % of polytrimethylene ether ester soft segment and about 20 to about 60 weight % polyamide hard segment. 
   
   
       6 . The carpet underlay of  claim 5  wherein the polyamide hard segments are joined by ester linkages to polytrimethylene ether soft segments prepared by reacting carboxyl terminated polyamide or diacid anhydride, diacid chloride or diester acid equivalents thereof and polyether glycol under conditions such that ester linkages are formed. 
   
   
       7 . The carpet underlay of  claim 6  wherein the carboxyl terminated polyamide is the polycondensation product of lactam, amino-acid or a combination thereof with dicarboxylic acid. 
   
   
       8 . The carpet underlay of  claim 1  wherein the barrier film comprises copolymer comprising polytrimethylene ether soft segments and polyurethane or polyurethane-urea hard segments. 
   
   
       9 . The carpet underlay of  claim 8  wherein the copolymer is a polyurethane or polyurethane-urea prepared from a reaction mixture comprising: (a) polytrimethylene ether glycol; (b) diisocyanate; and (c) diol or diamine chain extender. 
   
   
       10 . The carpet underlay of  claim 1  that is simultaneously impermeable to liquid deposited onto the underlay from above the barrier film, and permeable to moisture vapor at a moisture vapor transmission rate of at least 14.6 grams per square meter per twenty-four hours (14.6 g/m 2 /24 hours), the underlay being sufficiently durable to maintain liquid impermeability under a pressure of at least eight pounds per square inch (0.56 kg/m 2 ) as measured by a Modified Mullen Bursting Strength Test, and wherein the carpet underlay does not absorb liquid deposited onto the underlay from above the upper surface of the barrier film and allows moisture from below the lower surface of the cushion to pass through the underlay. 
   
   
       11 . The carpet underlay of  claim 1  further comprising a layer of polymeric adhesive material bonding the barrier film to the upper surface of the cushion. 
   
   
       12 . The carpet underlay of  claim 11  that is simultaneously impermeable to liquid deposited onto the underlay from above the barrier film, and permeable to moisture vapor at a moisture vapor transmission rate of at least 14.6 grams per square meter per twenty-four hours (14.6 g/m 2 /24 hours), the underlay being sufficiently durable to maintain liquid impermeability under a pressure of at least eight pounds per square inch (0.56 kg/m 2 ) as measured by a Modified Mullen Bursting Strength Test, whereby the carpet underlay does not absorb liquid deposited onto the underlay from above the upper surface of the barrier film and allows moisture from below the lower surface of the cushion to pass through the underlay. 
   
   
       13 . The carpet underlay of  claim 11  wherein the polymeric adhesive is a hot melt adhesive comprising copolymer that comprises polytrimethylene ether soft segments and hard segments selected from the group consisting of polyester, polyamide, polyurethane and polyurethane-urea. 
   
   
       14 . The carpet underlay of  claim 13  wherein the hard segment comprises an ester of at least one dicarboxylic acid selected from the group consisting of phthalic acid, isophthalic acid and terephthalic acid. 
   
   
       15 . The carpet underlay of  claim 13  wherein the polyamide hard segments are joined by ester linkages to polytrimethylene ether soft segments prepared by reacting carboxyl terminated polyamide or diacid anhydride, diacid chloride or diester acid equivalents thereof and polyether glycol under conditions such that ester linkages are formed. 
   
   
       16 . The carpet underlay of  claim 13  wherein the copolymer is a polyurethane or polyurethane-urea prepared from a reaction mixture comprising: (a) polytrimethylene ether glycol; (b) polyisocyanate; and (c) diol or diamine chain extender. 
   
   
       17 . The carpet underlay of  claim 2  wherein the foamed polyurethane or polyurethane urea is prepared from a reaction mixture comprising: (a) polytrimethylene ether glycol (b) polyisocyanate and (c) blowing agent. 
   
   
       18 . The carpet underlay of  claim 17  wherein the reaction mixture further comprises vegetable oil polyol. 
   
   
       19 . The carpet underlay of  claim 18  wherein the amount of vegetable oil polyol is from about 10 to about 90 weight % of the total amount of polyols. 
   
   
       20 . Carpet having a tufted yarn face and an underside, wherein the yarn face comprises polytrimethylene terephthalate fibers and the underside is affixed to the carpet underlay of  claim 1 . 
   
   
       21 . A process for rendering a carpet or foamed carpet underlay cushion having an upper and a lower surface impermeable to liquids and permeable to moisture vapor, comprising providing a carpet having an underside; providing a cushion having an upper surface; and placing between the underside of the carpet and the upper surface of the cushion a barrier film that is impermeable to liquids and permeable to moisture vapor and that comprises copolymer comprising polytrimethylene ether segments and segments selected from the group consisting of polyester, polyamide, polyurethane and polyurethane-urea. 
   
   
       22 . The process of  claim 21  wherein the barrier film has a thickness in the range from about 0.5 to about 1.5 mils. 
   
   
       23 . The process of  claim 21  wherein the barrier film is bonded to the upper surface of the cushion with a layer of polymeric adhesive. 
   
   
       24 . The process of  claim 21  wherein the foamed cushion comprises foamed polyurethane or polyurethane urea comprising poly(trimethylene ether) blocks as a soft segment. 
   
   
       25 . The process of  claim 21  wherein the carpet face yarn comprises fibers comprising polytrimethylene terephthalate.